Hello, Desert Star Systems currently manufacturers four pop-up satellite tags (also know as PSAT or PAT tags). These tags include the SeaTag-SAM, SeaTag-GEO, SeaTag-3D, and SeaTag-MOD each being manufactured and designed for a specific use purpose/application. SeaTag-SAM: Stock Assessment and Mortality SeaTag-GEO: High accuracy GEOlocation – uses magnetics SeaTag-3D: High accuracy geolocation in addition to vertical migration via Depth sending SeaTag-MOD: The be-all / do-all tag which has everything you could imagine in a pop-up tag while being built to support a larger sample size…as compared to other PSAT tags from our competitors (xTag and miniPAT for example). Regards, Thomas Gray